The common name for the domestic dog is simply "dog." Scientifically classified as Canis lupus familiaris, dogs have been bred for thousands of years for various roles, including companionship, work, and assistance. Known for their loyalty and ability to form strong bonds with humans, dogs are often referred to as "man's best friend." They come in a wide variety of breeds, each with distinct characteristics, temperaments, and purposes, ranging from herding sheep to providing security or serving as service animals. Their versatility, intelligence, and social nature make them one of the most popular pets worldwide.